The aim of the proposed research is to provide an econometric framework for the integrated analysis of population problems. Econometric models relating to fertility, investment in human capital and female labor force participation over the life cycle will be developed and tested using various bodies of data, with particular emphasis on the simultaneous character of these decisions. We choose to use data from Quebec, the Dominican Republic, Columbia and Chile because of the unusual richness of the information they contain. The Quebec survey includes, in addition to the customary fertility questions, a detailed work history for each of the women interviewed. The other bodies of data also contain important female labor supply information which is not available in conventional fertility surveys. We emphasize that the behavioral relationships to be studied are of a general nature, and therefore the econometric framework and empirical results are applicable to the population problems of the United States.